To prevent air leakage, the tone holes must be closed exactly to ensure that the wooden flute for sale keys are sealed. Then a precise tone can be created. This can only be done by making sure that the key and tone hole are level, and that the pad is free of holes and creases.
You do this by placing the pads correctly, then bent the keys to test them continuously until you achieve the best seal. There are many ways to test the seal. The most popular way to test the seal is with a piece of cigarette paper. Place the strip between the pad’s rim and the tone hole. Close the key to check if it is secure or falls out. If the paper slips, it means that air can escape from that space. This will result in loss of sound and volume. To examine the hole, I prefer to use a jeweler’s eye loop rather than cigarette paper. I can see the hole better through the magnification which makes it easier and faster.
It was very frightening to bend the keys to level them. A $300.00 or more instrument is being worked on. You take a pair flute pliers and bend the key so that it fits perfectly over the hole. You may occasionally crack the keys. This can be very distressing at first, but once you realize that you are supposed to be able fix broken keys, it becomes a minor issue. You can be confident that you can repair anything once you understand that the entire flute had to have been made and soldered together. We have successfully recovered flutes that had been stepped on, sat upon, jammed in doors, etc.
Okay, so we removed all bends and dents. This is an art form all its own. We checked that the springs were in good condition and maintained the correct tension. We checked, replaced, and seated all necessary pads. We bent and leveled the pads and keys over the tone holes, so we can get as close as possible to a perfect seal.
Next, we clamp the keys closed to create a deep impression in the pad. This seals the area. To remove wrinkles from new pads, we first use a small pad iron. Next, soak the pads in alcohol (this is only one method). Use the individual key clamps. After that, place the flute into a pad oven for several hours. There are many types of pad ovens. I use a narrow, long leak light that I place in the flute. Then I place it in a wooden container. Some people don’t use an oven.
The flute will then seal well and play beautifully. You’ll get great volume with no leaks or hissing.